Application and Advantages/Disadvantages of Lateral Powder Feeding and Coaxial Powder Feeding Laser Cladding
Laser cladding is a metal surface modification technology that uses high-energy laser beams to melt cladding powder and the substrate surface, forming a metallurgical bonding layer. This process significantly enhances the substrate's wear resistance, corrosion resistance, and other properties. In terms of powder feeding methods, traditional technologies mainly adopt lateral and coaxial powder feeding, while high-speed laser cladding derives a central powder feeding method to further optimize process efficiency.
Principle of Lateral Powder Feeding
Lateral powder feeding, also known as side powder feeding, sets the powder feeding device independently from the laser beam. Metal powder is pre-deposited on the substrate surface by gravity, and then the laser beam scans and melts the powder to complete cladding. This technology uses rectangular laser spots, matches with semiconductor or fiber lasers, and requires a fixed angle between the powder feeding nozzle and the laser head.
Characteristics of Lateral Powder Feeding
Lateral powder feeding improves material utilization through pre-deposited powder and eliminates inert gas consumption, reducing costs. The rectangular spot design enhances cladding efficiency. However, it relies on powder self-protection, limiting applicable materials; the cladding layer surface has significant undulations, requiring subsequent processing, and is unsuitable for inclined surfaces or inner holes.
Principle of Coaxial Powder Feeding
Coaxial powder feeding outputs laser from the center, with metal powder distributed in a ring or multiple beams around the laser. The cladding head integrates protective gas, powder, and cooling water channels. In traditional cladding, the laser and powder act on the substrate surface; in high-speed cladding, their intersection is above the workpiece, allowing powder to fully absorb laser energy before falling into the molten pool.
Characteristics of Coaxial Powder Feeding
Coaxial powder feeding protects the molten pool with inert gas, reducing oxidation and improving cladding layer crack resistance. Its integrated design of powder feeding and laser facilitates automation, adapting to cladding in any direction. However, pneumatic powder feeding causes material loss, narrow channels are prone to blockage, maintenance costs are high, and system stability is affected by structural complexity.
Core Components of laser Cladding System
Application Comparison
Lateral powder feeding suits surface strengthening and remanufacturing of large-area, simple-shaped parts like hydraulic cylinders and rolling rolls, leveraging efficiency and cost advantages. Coaxial powder feeding is more suitable for high-precision or complex-shaped parts such as spindles and gears, as well as metal 3D printing and gradient material preparation, excelling in surface quality and adaptability.